[Coco] Coco Digest, Vol 55, Issue 13

[carl j england]

> Message: 8
> Date: Sun, 06 Jan 2008 23:01:33 -0500
> From: Ghislain Harvey <ghislainharvey at videotron.ca>
> Subject: Re: [Coco] Is there any disk utility that allow 
> to        copy
>         selected        track        only?
> To: 'CoCoList for Color Computer Enthusiasts' 
> <coco at maltedmedia.com>
> Message-ID: <000001c850e1$fdd97610$f98c6230$@ca>
> Content-Type: text/plain; charset=iso-8859-1
> 
> Thanks for all those valuable information you gave me.
> The only problem left for me is that for a unknown reason I can't 
> recreate
> it on a real coco. It freeze when formatting track0.
> Maybe I do not copy correctly the DSK image to the real coco disk.
> Even with keil emulator , I am unable to recreate the disk.
> Maybe there is something wrong with the defeater.
> Ghislain
> 
> -----Message d'origine-----
> De?: coco-bounces at maltedmedia.com 
> [mailto:coco-bounces at maltedmedia.com] De
> la part de Robert Gault
> Envoy??: January-06-08 10:17 PM
> ??: CoCoList for Color Computer Enthusiasts
> Objet?: Re: [Coco] Is there any disk utility that allow to copy 
> selected
> track only?
> 
> Darren A. wrote:
> 
> >>Yes it is copy protected. I'm trying to rebuilt z89 from the 
> downunder. I
> >>think there might be some bug in the code. Btw it use the defeater 
> but
> there
> >>are disk error while the program is trying to write sector higher 
> than 18.
> >>Here is the direct link to the files. When you uncompress it its 
> under SRB
>
>>http://coco.clubltdstudios.com/downunder/RSDOS/Sundog-Games/Sundog/game
s.z
> zz
> >>.zip
> >>Thanks and tell me if you are able to make it work on emulator or 
> real
> coco.
> >>Ghislain
> >>
> > 
> > 
> > --
> > 
> > Are you running this on a real CoCo3 or an emulator?
> > 
> > I haven't tried it on a real CoCo3, but it looks like it may 
> require a
> double-sided drive. The patches being applied to the disk show that 
> it is
> writing sectors 22 through 25 to both sides 0 and 1.
> > 
> > Doing this on an emulator would require using the DMK image format 
> instead
> of the JVC image provided. However, I don't know if either MESS or 
> the VCC
> emulator will correctly emulate a program that formats a track in a
> non-standard way to a DMK image.
> > 
> > If I knew the format of the patch files produced by The Defeater, 
> I could
> possibly use them to create a DMK image directly, or modify the 
> CoCoDisk
> utility to write the patches to a real floppy disk.
> > 
> > Darren
> > 
> > 
> 
> That file is too large for me to want to download over a dial-up 
> connection. However, I have been sent a DMK version of the game and 
> it 
> is single sided.
> 
>   Using Defeater on that image shows tracks 0-25 and 33 are copy 
> protected. Some of them have no content other than $00. Others have 
> 
> 512byte sectors 22-26.
>   Even though the disk is single sided, the track headers have some 
> 
> sectors labeled as side 1. That does not mean the disk is double 
> sided 
> but that the sectors are deliberately mislabeled.
> 
> Far as I can tell, the Defeater Patch.bin format is a byte per byte 
> copy 
> of the track so that writing it back during a Format will recreate 
> the 
> track.
> 
> --
> Coco mailing list
> Coco at maltedmedia.com
> http://five.pairlist.net/mailman/listinfo/coco
> 
> 
> 
> ------------------------------> 
> Over the past few weeks, some people on this alias wanted to create 
> some
> adventure games.  As a place to get started, would anyone want to 
> port the
> original "Colossal Cave" to the coco?  The Fortran code is at
> http://jerz.setonhill.edu/if/crowther/, and if you browse up from 
> there you
> can see all kinds of details on it.
> 
> Anyway, porting other code is sometimes easier than creating a 
> project from
> scratch.
> 
> Just a thought,
> John Guin
> 
> 
> --
> Coco mailing list
> Coco at maltedmedia.com
> http://five.pairlist.net/mailman/listinfo/coco
> 
> 
>        
> ---------------------------------
> Looking for last minute shopping deals?  Find them fast with Yahoo! 
> Search.
> 
The Defeater will copy "Z-89", but it takes patience

tracks 0 and 33 both contain data that is written directly to the track
without any sectors.
tracks 1 thru 25 eack contain 9 sectors of 512k bytes each.  the problem
is that sectors numbered 16, 17, 18, 19 are duplicated on side 0 but
claim to be on side 1 also.  sector 1a only claims to be on side 0.
(i think The Defeater has a "feature" (ok--call it a bug!) that displays
the track and sector numbers in hex, but must be entered in decimal
(could be wrong about this--been a while since using The Defeater))

the decimal values of the sectors in question would be 22 side 0, 22 side
1, 23 side 0, 23 side 1, 24 side 0, 24 side 1, 25 side 0, 25 side 1, 26
side 0.

the sectors will have to be copied for all tracks (1-25)

you can't use any "normal" disk basic utilities to copy the sectors
because the coco doesn't "normally" check the "side" information so there
would be no way to ensure that the correct data was written to the
correct sectors (on those that are duplicated).

this is not a difficult disk to copy--but it does take time and patience.

carl